Plasma display panel

ABSTRACT

A plasma display panel includes a first substrate, a second substrate mounted opposing the first substrate with a predetermined gap therebetween to thereby form a vacuum assembly, and barrier ribs formed between the first substrate and the second substrate, the barrier ribs defining discharge cells. The barrier ribs are formed so as to provide radial exhaust paths for each of the discharge cells. Moreover, the barrier ribs are configured dimensioned and arranged so as to maximize the exhaust efficiency of the plasma display panel.

CLAIM OF PRIORITY

[0001] This application makes reference to, incorporates the sameherein, and claims all benefits accruing under 35 U.S.C. §119 from anapplication entitled PLASMA DISPLAY PANEL filed with the KoreanIndustrial Property Office on 17 Dec. 2002 and there duly assignedSerial No. 2002-0080804, and an application entitled PLASMA DISPLAYPANEL filed with the Korean Industrial Property Office on Jan. 15, 2003and there duly assigned Serial No. 2003-0002682.

BACKGROUND OF THE INVENTION

[0002] 1. Technical Field

[0003] The present invention relates to a plasma display panel and, moreparticularly, to barrier ribs of a plasma display panel.

[0004] 2. Related Art

[0005] A plasma display panel (PDP) typically includes barrier ribs thatdefine discharge cells. The two main types of barrier ribs are closedbarrier ribs and open barrier ribs. The open barrier ribs are generallyformed in a stripe configuration. Since discharge cells formed betweensuch stripe-type barrier ribs are in communication (i.e., the dischargecells between each pair of adjacent barrier ribs are in communication),exhaust of the PDP and sealing of discharge gas within the PDP arerelatively easily performed during manufacture.

[0006] With the closed barrier ribs, on the other hand, the dischargecells are not in communication. That is, the barrier ribs are formedinto individual units having a quadrilateral, hexagonal, or other shape.With the closed barrier ribs, the discharge cells are separately formedfor each pixel, and phosphor material is formed over all inner surfacesof barrier ribs that form each pixel.

[0007] In the first PDPs that utilized such closed barrier ribs, a gapformed between a distal end of the barrier ribs and the substrateopposing the substrate on which the barrier ribs are formed was used asan exhaust path. The gap was formed by adjusting the height of thebarrier ribs or by forming depressions at predetermined locations ofdistal end areas of the barrier ribs. However, because of the minimalsize of the gap, the resulting exhaust resistance necessitated the useof a significant amount of time to exhaust the PDP. This reduced overallmanufacturing efficiency.

[0008] Various configurations have been disclosed to overcome theseproblems. For example, Japanese Laid-Open Patent No. Heisei 4-274141discloses a structure in which open stripe-type barrier ribs and closedlattice-type barrier ribs are combined to reduce exhaust resistance.However, with such a combinational structure, the process of formingeach barrier rib on the substrate during PDP manufacture is complicated.With this structure, productivity is reduced to such an extent that massproduction is made difficult.

[0009] Japanese Laid-Open Patent No. Heisei 2002-83545 discloses a PDPin which closed barrier ribs are formed using a material that has a heatshrink property. The barrier ribs are formed having areas of lesserheight that function as exhaust paths to thereby form a mesh-typestructure of the exhaust paths. Although it is claimed that such abarrier rib structure reduces exhaust resistance during the exhaustprocess, in practice, there is a limited number of paths through whichexhaust may occur as a result of the mesh configuration. This may resultin insufficient exhaust of the PDP.

SUMMARY OF THE INVENTION

[0010] The present invention provides a plasma display panel includingbarrier ribs that maximize exhaust efficiency.

[0011] More particularly, the present invention provides a plasmadisplay panel including barrier ribs that enable improvements inbrightness through the efficient use of discharge cells.

[0012] In one embodiment, the present invention provides a plasmadisplay panel including a first substrate, a second substrate mountedopposing the first substrate with a predetermined gap therebetween tothereby form a vacuum assembly, and barrier ribs formed between thefirst substrate and the second substrate, the barrier ribs definingdischarge cells. Radial exhaust paths are formed in the barrier ribs foreach of the discharge cells.

[0013] The discharge cells are formed in a closed configuration by thebarrier ribs, and the discharge cells are arranged in a lattice patternor a delta pattern.

[0014] In another embodiment, the present invention is a plasma displaypanel including a first substrate, a second substrate mounted opposingthe first substrate with a predetermined gap therebetween to therebyform a vacuum assembly, and barrier ribs formed on the second substrateand extending a predetermined distance in a direction toward the firstsubstrate, the barrier ribs defining discharge cells. A plan view of thebarrier ribs is such that, if imaginary lines are formed bisectingdistal end surfaces of the barrier ribs, the imaginary lines form aplurality of multilateral shapes that encompass each of the dischargecells to thereby form the discharge cells into the multilateral shapes.Also, if a radius of a first inscribed circle drawn in areas of thebarrier ribs corresponding to corner portions of the multilateral shapesof the discharge cells is R, and a radius of a second inscribed circledrawn in areas corresponding to predetermined points between the cornerportions of the multilateral shapes of the discharge cells is r, thefollowing condition is satisfied:

R>r.

[0015] Alternatively, the barrier ribs may be formed so as to satisfythe following condition:

R>2r.

[0016] The barrier ribs are made of a material that has a heat shrinkproperty, and widths of the distal end surfaces of the barrier ribsvary, in a continuous manner or in stages, along a direction in whichthe barrier ribs are formed.

[0017] Further, exhaust paths are formed in the barrier ribs such thatone of the exhaust paths is formed in areas of the barrier ribscorresponding to each side of the multilateral discharge cells. Theexhaust paths are formed in the distal ends of the barrier ribs.

[0018] The plasma display panel further includes sub exhaust pathsformed in areas of the barrier ribs where corner portions of themultilateral shapes of the discharge cells converge. The sub exhaustpaths are realized by exhaust grooves formed in the barrier ribs.

[0019] In another embodiment, the present invention is a plasma displaypanel including a first substrate, a second substrate mounted opposingthe first substrate with a predetermined gap therebetween to therebyform a vacuum assembly, and barrier ribs formed on the second substrateand extending a predetermined distance in a direction toward the firstsubstrate, the barrier ribs defining discharge cells. A plan view of thebarrier ribs is such that, if imaginary lines are formed bisectingdistal end surfaces of the barrier ribs, the imaginary lines form aplurality of multilateral shapes that encompass each of the dischargecells to thereby form the discharge cells into the multilateral shapes.

[0020] Also, the height of the barrier ribs, measured from where theyare formed on the second substrate to the distal end of the same, isgreater at areas corresponding to corner portions of the multilateralshapes of the discharge cells than at areas between the corner portionsof the multilateral shapes of the discharge cells.

[0021] The height of the barrier ribs is at a maximum at areascorresponding to the corner portions of the multilateral shapes of thedischarge cells, and the height of the barrier ribs is at a minimum atpredetermined points between the corner portions of the multilateralshapes of the discharge cells.

[0022] A width of the distal ends of the barrier ribs at areascorresponding to the corner portions of the multilateral shapes of thedischarge cells is greater than the width of the distal ends of thebarrier ribs at areas between the corner portions of the multilateralshapes of the discharge cells.

[0023] Further, the heights of the barrier ribs vary in a continuousmanner starting from where the heights are maximum and decreasing untilreaching the minimum heights.

[0024] The present invention is more specifically described in thefollowing paragraphs by reference to the drawings attached only by wayof example. Other advantages and features will become apparent fromfollowing description and from the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] A more complete appreciation of the invention, and many of theattendant advantages thereof, will be readily apparent as the samebecomes better understood by reference to the following detaileddescription when considered in conjunction with the accompanyingdrawings in which like reference symbols indicate the same or similarcomponents, wherein:

[0026]FIG. 1 is a partial exploded perspective view of a plasma displaypanel according to a first embodiment of the present invention;

[0027]FIG. 2 is a plan view showing a structure of barrier ribs of FIG.1;

[0028]FIGS. 3A and 3B are sectional views taken along lines A-A and B-Bof FIG. 2;

[0029]FIG. 4 is a plan view showing a structure of barrier ribsaccording to a second embodiment of the present invention;

[0030]FIGS. 5, 6, and 7 are plan views showing a structure of barrierribs according to a third embodiment of the present invention;

[0031]FIG. 8 is a partial exploded perspective view of a plasma displaypanel according to a fourth embodiment of the present invention;

[0032]FIG. 9 is an enlarged perspective view of a sub exhaust path ofFIG. 8; and

[0033]FIG. 10 is a partial plan view of a plasma display panel accordingto a fifth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0034] Embodiments of the present invention will now be described indetail with reference to the accompanying drawings.

[0035]FIG. 1 is a partial exploded perspective view of a plasma displaypanel according to a first embodiment of the present invention, FIG. 2is a plan view showing a structure of barrier ribs of FIG. 1, and FIGS.3A and 3B are sectional views taken along lines A-A and B-B of FIG. 2.

[0036] With reference to the drawings, the plasma display panel (PDP)according to the first embodiment of the present invention includes afirst substrate 10 and a second substrate 12 opposing one another with apredetermined gap therebetween. A vacuum assembly is formed by thecombination of the first substrate 10 and the second substrate 12.

[0037] Address electrodes 14 are formed in a predetermined pattern(e.g., a stripe pattern) and at predetermined intervals on the secondsubstrate 12. A first dielectric layer 16 is formed on the secondsubstrate 12 and covers the address electrodes 14. Further, barrier ribs18 are formed on the first dielectric layer 16 and in a predeterminedpattern to define a plurality of discharge cells 17.

[0038] In the first embodiment, the barrier ribs 18 are made of a glassmaterial having a low melting point. Regarding a plan view formation ofthe barrier ribs 18, with reference to FIGS. 1 and 2, in a state whereimaginary lines L are formed bisecting distal end surfaces of thebarrier ribs 18, the imaginary lines L form a plurality of multilateralshapes that encompass each of the discharge cells 17. In the firstembodiment, the imaginary lines L are formed into a plurality ofquadrilateral shapes.

[0039] The barrier ribs 18 include row sections 18 a extending in adirection substantially perpendicular to the direction in which theaddress electrodes 14 are formed, and column sections 18 b extending ina direction substantially parallel to the direction in which the addresselectrodes 14 are formed. Areas where the row sections 18 a and thecolumn sections 18 b intersect, that is, areas of the barrier ribs 18between four adjacent discharge cells 17, occupy a greater space thanother areas of the barrier ribs 18. The formation of the barrier ribs18, and, in particular, the relative widths of the barrier ribs 18, willbe described in greater detail below.

[0040] As an example, areas of the barrier ribs 18 between four adjacentdischarge cells 17 are the greatest among all areas of the barrier ribs18, while areas of the barrier ribs 18 corresponding to centers of longsides and short sides of adjacent discharge cells 17 are the smallestamong all areas of the barrier ribs 18. In particular, a radius R of afirst inscribed circle C1 (see FIG. 2) drawn in one of the areas of thebarrier ribs 18 between four adjacent discharge cells 17 is greater thana radius r of a second inscribed circle C2 (see FIG. 2) drawn in areascorresponding to the center of the long sides and short sides ofadjacent discharge cells 17. That is, these radii R and r satisfy thecondition R>r, and more preferably satisfy the condition R>2r.

[0041] With reference to FIGS. 3A and 3B, areas where the secondinscribed circles C2 are drawn, that is, areas of the barrier ribs 18corresponding to centers of the long sides and short sides of adjacentdischarge cells 17 with the smallest widths, have a height H1 that isthe smallest among all areas of the barrier ribs 18, while areas of thebarrier ribs 18 between four adjacent discharge cells 17 have a heightH2 that is the greatest among all areas of the barrier ribs 18.

[0042] With this configuration, gaps of predetermined dimensions areformed between the first substrate 10 and the distal ends of the rowsections 18 a and the column sections 18 b of the barrier ribs 18 by thedifference in the heights H1 and H2. Preferably, the difference in theheights H1 and H2 is between 5 and 10 μm. These gaps function as exhaustpaths P through which air inside the PDP travels when forming a vacuumin the same during manufacture. As a result, radial paths P are providedfor each of the discharge cells 17. In the first embodiment, fourexhaust paths P are provided for each discharge cell 17.

[0043] The barrier ribs 18 are formed by a sandblast process, which iscommonly used in the manufacture of PDPs. If a minimum width of thebarrier ribs 18 that can be formed using the sandblast process is m, theradius r of the second inscribed circle C2 described above satisfies thecondition:

2r>m.

[0044] Further, with reference to FIG. 2, the width of the row sections18 a and the column sections 18 b of the barrier ribs 18 may becontinuously (i.e., not abruptly and not in steps) made larger as thedistance from their centers (where the inscribed circles C2 are formed)is increased. Also, with reference to FIGS. 3A and 3B, the heights ofthe row sections 18 a and the column sections 18 b may be continuouslyreduced starting from areas thereof where the heights are H2 and movingtoward areas thereof where the heights are H1.

[0045] The barrier ribs 18 structured as described above are producedaccording to the following manufacturing method of the presentinvention.

[0046] First, in a state where the address electrodes 14 and the firstdielectric layer 16 are formed on the second substrate 12, a barrier ribmaterial layer of a predetermined thickness is realized through a paste,which is formed by uniformly mixing a vehicle and a glass powder havinga low melting point, and the barrier rib material layer is formed on thefirst dielectric layer 16 using a screen printing method or a laminatemethod. The glass powder of a low melting point may be made, forexample, of a material containing 50˜60 wt % of Pbo, 5˜10 wt % of B₂O₃,10˜20 wt % of SiO₂, 15˜25 wt % of Al₂O₂, and 5% or less of CaO.

[0047] Following the drying of the barrier rib material layer, aphotosensitive dry film is formed or a resist material is deposited.Then, using a photolithography process that includes exposure anddevelopment, a cut mask is formed in a lattice pattern corresponding tothe desired shape of barrier ribs. The dimensions of the mask patternare set to be greater than the desired dimensions of the barrier ribssince thermal contraction of the barrier rib material layer occurs.

[0048] Next, using a sandblast process, non-masked portions of thebarrier rib material layer are removed until the dielectric layer isexposed. Heating and baking are then performed to thereby complete theformation of the barrier ribs.

[0049] The cut mask has a pattern corresponding to the various shapes ofthe barrier ribs 18 as described above.

[0050] Red, green, and blue phosphor layers 20R, 20G, and 20B (seeFIG. 1) are deposited on areas of the first dielectric layer 16positioned within the discharge cells 17 and on inner surfaces of thebarrier ribs 18 within the discharge cells 17 to thereby formcorresponding pixels (i.e., R, G, and B pixels). In the firstembodiment, the discharge cells 17 are arranged in a lattice patternwherein each of the discharge cells is individually formed in fullyclosed units by the barrier ribs 18.

[0051] Further, formed on a surface of the first substrate 10, opposingthe second substrate 12, are discharge sustain electrodes 22 thatinclude common electrodes 22 a, scanning electrodes 22 b, and buselectrodes 22 c formed on each of the common electrodes 22 a and thescanning electrodes 22 b The common electrodes 22 a and the scanningelectrodes 22 b are made of a transparent material, such as indium tinoxide (ITO), and the bus electrodes 22 c are made of a conductivematerial, such as silver (Ag) or gold (Au).

[0052] The discharge sustain electrodes 22 are formed in a directionsubstantially perpendicular to the direction in which the addresselectrodes 14 are formed. A second dielectric layer 24 is formed on thefirst substrate 10 covering the discharge sustain electrodes 22, and aprotective layer made of MgO is formed over the second dielectric layer24. The protective layer 26 acts to protect the discharge sustainelectrodes 22, and functions also to aid discharge by emitting secondaryelectrons.

[0053] In the PDP having the closed barrier rib structure as describedabove, there are provided radial exhaust paths P for each of thedischarge cells 17 such that exhaust efficiency is significantlyimproved over the prior art.

[0054]FIG. 4 is a plan view showing the structure of barrier ribsaccording to a second embodiment of the present invention. Barrier ribs28 according to the second embodiment have the basic structure of thebarrier ribs of the first embodiment. However, row sections 28 a of thebarrier ribs 28 that define discharge cells 27 are positioneddifferently. In particular, the row sections 28 a of the barrier ribs 28of adjacent discharge cells 27 (i.e., adjacent in a direction in whichthe row sections 28 a are formed) are offset and not aligned as in thefirst embodiment. As a result, the discharge cells 27 defined by thebarrier ribs 28 are arranged in a delta pattern.

[0055]FIGS. 5, 6, and 7 are plan views showing the structure of barrierribs according to a third embodiment of the present invention. FIG. 5shows a structure in which imaginary lines L bisecting distal endsurfaces of barrier ribs 38 are formed into a plurality of hexagonalshapes. Stated differently, the barrier ribs 38 are formed to define aplurality of discharge cells 37 such that the discharge cells 37 areformed as individual, closed units in the shape of a hexagon or asimilar form. As a result of this configuration, the discharge cells 37may be arranged in a delta configuration.

[0056] In the third embodiment, areas of the barrier ribs 38 between anythree, mutually adjacent discharge cells 37 occupy the largest area andhave the greatest height when compared to other areas of the barrierribs 38, that is, main sections 38 a of the barrier ribs 38. Thisresults in the formation of exhaust paths in the main sections 38 a ofthe barrier ribs 38. Since there is a larger number of exhaust paths foreach of the discharge cells 37 than in the first embodiment, an evengreater improvement in exhaust efficiency is realized.

[0057] The basic configuration of FIGS. 5, 6 and 7 shows the barrierribs 38 defining the discharge cells 37 such that the discharge cells 37are formed as closed, 12-sided individual units. As shown in FIG. 6, thetwelve sides forming each of the discharge cells 37 are substantiallyequal in length, and the barrier ribs 38 are placed in relation to oneanother such that the main sections 38 a between adjacent dischargecells 37 have a width that increases as the distance from the center ofthe main sections 38 a increases.

[0058] In FIG. 7, the twelve sides forming each of the discharge cells37 are not equal in length. That is, the sides that form the mainsections 38 a are longer than the sides in areas where three, mutuallyadjacent discharge cells 37 converge. Therefore, the widths of thebarrier ribs 38 along the main sections 38 a remain constant.

[0059]FIG. 8 is a partial exploded perspective view of a plasma displaypanel according to a fourth embodiment of the present invention. Likereference numerals will be used for elements of the fourth embodimentidentical to those of the first embodiment.

[0060] The PDP of the fourth embodiment of the present inventionutilizes the same basic structure as the PDP of the first embodiment.However, sub exhaust paths 40 are formed at areas where the row sections18 a and the column sections 18 b intersect, that is, at areas of thebarrier ribs 18 between four adjacent discharge cells 17.

[0061] The sub exhaust paths 40 are formed to enable communicationbetween adjacent discharge cells 17 to thereby improve the exhaustprocess. With reference also to FIG. 9, the sub exhaust paths 40 arerealized by forming exhaust grooves in the barrier ribs 18. The subexhaust paths 40 may be formed in a simple manner using an etchingprocess. As an example, the exhaust grooves may be formed to a width of10˜100 μm and a depth of 10˜130 μm.

[0062] With the PDP of the fourth embodiment, in addition to the radialexhaust paths formed by the particular configuration of the row sections18 a and the column sections 18 b of the barrier ribs 18 as describedwith reference to the first embodiment, the sub exhaust paths 40 act toeven further improve exhaust efficiency.

[0063]FIG. 10 is a partial plan view of a plasma display panel accordingto a fifth embodiment of the present invention. In the fifth embodiment,sub exhaust paths 50 are formed on barrier ribs 48 in the case where thebarrier ribs 48 are formed to realize a delta pattern of dischargecells. Although the sub exhaust paths 50 are formed at each corner areabetween adjacent discharge cells, it is also possible to form the subexhaust paths 50 at other selective locations.

[0064] While the present invention has been illustrated by thedescription of embodiment thereof, and while the embodiments have beendescribed in considerable detail, it is not intended to restrict or inany way limit the scope of the appended claims to such detail.Additional advantages and modifications will readily appear to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the special details, representative apparatus and method,and illustrative examples shown and described. Accordingly, departuresmay be made from such details without departing from the sprit and scopeof the general inventive concept.

What is claimed is:
 1. A plasma display panel, comprising: a firstsubstrate; a second substrate opposing the first substrate with apredetermined gap therebetween to form a vacuum assembly; and barrierribs formed between the first substrate and the second substrate, thebarrier ribs defining discharge cells; wherein the barrier ribs formradial exhaust paths for each of the discharge cells.
 2. The plasmadisplay panel of claim 1, wherein the discharge cells are formed in aclosed configuration by the barrier ribs.
 3. The plasma display panel ofclaim 2, wherein the discharge cells are arranged in a lattice pattern.4. The plasma display panel of claim 2, wherein the discharge cells arearranged in a delta pattern.
 5. A plasma display panel, comprising: afirst substrate; a second substrate opposing the first substrate with apredetermined gap therebetween to form a vacuum assembly; and barrierribs formed on the second substrate and extending a predetermineddistance in a direction toward the first substrate, the barrier ribsdefining discharge cells; wherein a plan view of the barrier ribs issuch that, if imaginary lines are formed bisecting distal end surfacesof the barrier ribs, the imaginary lines form a plurality ofmultilateral shapes that encompass each of the discharge cells so as tothereby form the discharge cells into the multilateral shapes; andwherein, if a radius of a first inscribed circle drawn in areas of thebarrier ribs corresponding to corner portions of the multilateral shapesof the discharge cells is R, and a radius of a second inscribed circledrawn in areas corresponding to points between the corner portions ofthe multilateral shapes of the discharge cells is r, the followingcondition is satisfied: R>r.
 6. The plasma display panel of claim 5,wherein the following condition is satisfied: R>2r.
 7. The plasmadisplay panel of claim 5, wherein the barrier ribs are made of amaterial having a heat shrink property.
 8. The plasma display panel ofclaim 5, wherein widths of the distal end surfaces of the barrier ribsvary in a continuous manner along a direction in which the barrier ribsare formed.
 9. The plasma display panel of claim 5, wherein widths ofthe distal end surfaces of the barrier ribs vary in stages along adirection in which the barrier ribs are formed.
 10. The plasma displaypanel of claim 5, wherein exhaust paths are formed in the barrier ribs,respective exhaust paths being formed in respective areas of the barrierribs corresponding to respective sides of the discharge cells.
 11. Theplasma display panel of claim 10, wherein the exhaust paths are formedin distal ends of the barrier ribs.
 12. The plasma display panel ofclaim 10, further comprising sub exhaust paths formed in areas of thebarrier ribs where the corner portions of the multilateral shapes of thedischarge cells converge.
 13. The plasma display panel of claim 12,wherein the sub exhaust paths are realized by exhaust grooves formed inthe barrier ribs.
 14. The plasma display panel of claim 5, furthercomprising sub exhaust paths formed in areas of the barrier ribs wherethe corner portions of the multilateral shapes of the discharge cellsconverge.
 15. The plasma display panel of claim 14, wherein the subexhaust paths are realized by exhaust grooves formed in the barrierribs.
 16. A plasma display panel, comprising: a first substrate; asecond substrate opposing the first substrate with a predetermined gaptherebetween to form a vacuum assembly; and barrier ribs formed on thesecond substrate and extending a predetermined distance in a directiontoward the first substrate, the barrier ribs defining discharge cells;wherein a plan view of the barrier ribs is such that, if imaginary linesare formed bisecting distal end surfaces of the barrier ribs, theimaginary lines form a plurality of multilateral shapes that encompasseach of the discharge cells so as to thereby form the discharge cellsinto the multilateral shapes; and wherein a height of each barrier ribmeasured from where it is formed on the second substrate to a distal endof said each barrier rib is greater at corner portions of themultilateral shapes of the discharge cells than at areas between thecorner portions of the multilateral shapes of the discharge cells. 17.The plasma display panel of claim 16, wherein the height of said eachbarrier rib is at a maximum at the corner portions of the multilateralshapes of the discharge cells.
 18. The plasma display panel of claim 16,wherein the height of said each barrier rib is at a minimum at pointsbetween the corner portions of the multilateral shapes of the dischargecells.
 19. The plasma display panel of claim 18, wherein the points aresubstantially at centers between any two corner portions of themultilateral shapes of the discharge cells.
 20. The plasma display panelof claim 16, wherein a width of the distal end of said each barrier ribat areas corresponding to the corner portions of the multilateral shapesof the discharge cells is greater than the width of the distal end ofsaid each barrier rib at areas between the corner portions of themultilateral shapes of the discharge cells.
 21. The plasma display panelof claim 16, wherein, if a radius of a first inscribed circle drawn inareas of the barrier ribs corresponding to the corner portions of themultilateral shapes of the discharge cells merge is R, and a radius of asecond inscribed circle drawn in areas corresponding to points betweenthe corner portions of the multilateral shapes of the discharge cells isr, the following condition is satisfied: R>r.
 22. The plasma displaypanel of claim 21, wherein the following condition is satisfied: R>2r.23. The plasma display panel of claim 16, wherein the barrier ribs aremade of a material having a heat shrink property.
 24. The plasma displaypanel of claim 16, wherein the height of said each barrier rib is at amaximum at the corner portions of the multilateral shapes of thedischarge cells, the height of said each barrier rib is at a minimum atpoints between the corner portions of the multilateral shapes of thedischarge cells, and the heights of the barrier ribs vary in acontinuous manner starting from maximum heights to minimum heights. 25.The plasma display panel of claim 16, wherein exhaust paths are formedin the barrier ribs, respective exhaust paths being formed in respectiveareas of the barrier ribs corresponding to respective sides of thedischarge cells.
 26. The plasma display panel of claim 25, wherein theexhaust paths are formed in the distal ends of the barrier ribs.
 27. Theplasma display panel of claim 25, further comprising sub exhaust pathsformed in areas of the barrier ribs where the corner portions of themultilateral shapes of the discharge cells converge.
 28. The plasmadisplay panel of claim 27, wherein the sub exhaust paths are realized byexhaust grooves formed in the barrier ribs.
 29. The plasma display panelof claim 16, wherein the discharge cells are formed in a closedconfiguration by the barrier ribs.
 30. The plasma display panel of claim29, wherein the discharge cells are arranged in a lattice pattern. 31.The plasma display panel of claim 29, wherein the discharge cells arearranged in a delta pattern.
 32. The plasma display panel of claim 16,further comprising sub exhaust paths formed in areas of the barrier ribswhere the corner portions of the multilateral shapes of the dischargecells converge.
 33. The plasma display panel of claim 28, wherein thesub exhaust paths are realized by exhaust grooves formed in the barrierribs.
 34. A plasma display panel, comprising: a first substrate; asecond substrate opposing the first substrate with a predetermined gaptherebetween to form a vacuum assembly; and barrier ribs formed betweenthe first substrate and the second substrate, the barrier ribs definingdischarge cells; wherein the barrier ribs form exhaust paths for thedischarge cells and respective exhaust paths are formed in respectiveareas of the barrier ribs corresponding to respective sides of thedischarge cells.
 35. The plasma display panel of claim 34, wherein theexhaust paths are formed in distal ends of the barrier ribs.
 36. Theplasma display panel of claim 35, further comprising sub exhaust pathsformed in areas of the barrier ribs where the corner portions of thedischarge cells converge.
 37. The plasma display panel of claim 36,wherein the sub exhaust paths are realized by exhaust grooves formed inthe barrier ribs.
 38. The plasma display panel of claim 34, furthercomprising sub exhaust paths formed in areas of the barrier ribs wherethe corner portions of the discharge cells converge.
 39. The plasmadisplay panel of claim 38, wherein the sub exhaust paths are realized byexhaust grooves formed in the barrier ribs.
 40. A plasma display panel,comprising: a first substrate; a second substrate opposing the firstsubstrate with a predetermined gap therebetween to form a vacuumassembly; and barrier ribs formed between the first substrate and thesecond substrate, the barrier ribs defining discharge cells; wherein aheight of each barrier rib is greater at corner portions of thedischarge cells than at areas between the corner portions of thedischarge cells.
 41. The plasma display panel of claim 40, wherein theheight of said each barrier rib is at a maximum at the corner portionsof the discharge cells.
 42. The plasma display panel of claim 40,wherein the height of said each barrier rib is at a minimum at pointsbetween the corner portions of the discharge cells.
 43. The plasmadisplay panel of claim 42, wherein the points are substantially atcenters between any two corner portions of the discharge cells.
 44. Theplasma display panel of claim 40, wherein a width of the distal end ofsaid each barrier rib at areas corresponding to the corner portions ofthe discharge cells is greater than the width of the distal end of saideach barrier rib at areas between the corner portions of the dischargecells.
 45. The plasma display panel of claim 40, wherein, if a radius ofa first inscribed circle drawn in areas of the barrier ribscorresponding to the corner portions of the discharge cells merge is R,and a radius of a second inscribed circle drawn in areas correspondingto points between the corner portions of the discharge cells is r, thefollowing condition is satisfied: R>r.
 46. The plasma display panel ofclaim 45, wherein the following condition is satisfied: R>2r.
 47. Theplasma display panel of claim 40, wherein the barrier ribs are made of amaterial having a heat shrink property.
 48. The plasma display panel ofclaim 40, wherein the height of said each barrier rib is at a maximum atthe corner portions of the discharge cells, the height of said eachbarrier rib is at a minimum at points between the corner portions of thedischarge cells, and the heights of the barrier ribs vary in acontinuous manner starting from maximum heights to minimum heights. 49.The plasma display panel of claim 40, wherein exhaust paths are formedin the barrier ribs, respective exhaust paths being formed in respectiveareas of the barrier ribs corresponding to respective sides of thedischarge cells.
 50. The plasma display panel of claim 49, wherein theexhaust paths are formed in distal ends of the barrier ribs.
 51. Theplasma display panel of claim 49, further comprising sub exhaust pathsformed in areas of the barrier ribs where the corner portions of thedischarge cells converge.
 52. The plasma display panel of claim 51,wherein the sub exhaust paths are realized by exhaust grooves formed inthe barrier ribs.
 53. The plasma display panel of claim 40, wherein thedischarge cells are formed in a closed configuration by the barrierribs.
 54. The plasma display panel of claim 53, wherein the dischargecells are arranged in a lattice pattern.
 55. The plasma display panel ofclaim 53, wherein the discharge cells are arranged in a delta pattern.56. The plasma display panel of claim 40, further comprising sub exhaustpaths formed in areas of the barrier ribs where the corner portions ofthe discharge cells converge.
 57. The plasma display panel of claim 56,wherein the sub exhaust paths are realized by exhaust grooves formed inthe barrier ribs.